local s60 = math.sin( 60 / 180 * math.pi )
local c60 = math.cos( 60 / 180 * math.pi )
-- creates a table object having ptop, pleft and pright as points
-- and a "draw yourself" function
function equilateralTriangle( ptop, len )
return {
ptop = ptop,
pleft = ptop + p{ -len/2, -len*s60 },
pright = ptop + p{ len/2, -len*s60 },
draw =
function( self )
draw{
fill = black,
draw = none,
polyline{ self.ptop, self.pleft, self.pright, 'cycle' }
}
end
}
end
-- one step into the fractal
-- ptop: top point of triangle
-- len: current length
-- level: current fractal level
function drawFractal( ptop, len, level )
if level == 1
then
local t = equilateralTriangle( ptop, len )
t:draw( )
else
local ttop = equilateralTriangle( ptop, len / 2 )
drawFractal( ttop.ptop, len / 2, level - 1 )
drawFractal( ttop.pleft, len / 2, level - 1 )
drawFractal( ttop.pright, len / 2, level - 1 )
end
end
